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1.
Flotation has been used in industry for more than a half century as the primary technique for upgrading phosphate. While the flotation of phosphate was inefficient when oleic acid was used alone as a collector, therefore a mixed collector of oleic acid (HOl), linoleic acid (LA) and linolenic acid (LNA) was employed to improve the recovery of phosphate flotation. The batch flotation results showed that the optimal composition of the mixed collector was 54 wt.% HOl, 36 wt.% LA and 10 wt.% LNA. Additionally, the effect of pH on the mixed collector application was studied while considering the surface tension, contact angle and micro-flotation. The results showed that the mixed collector should be used at a pH of 9.5. Above a pH of 9.5, the adsorption of fatty acids dimers on the apatite surface hindered phosphate flotation. The influence of the mixed collector assembly on apatite flotation was also investigated. It was demonstrated that due to its low critical micelle concentration, a sufficiently hydrophobic apatite surface could be generated at a collector concentration of 60 mg/L. In addition, zeta potential experiments suggested that collector adsorption was governed by chemisorption. FTIR and XPS spectra studies further indicated that the chemical reaction involved the carboxyl groups of fatty acids and Ca species at the apatite surface for each fatty acid in the mixed collector.  相似文献   
2.
It is the aim of this paper to examine the effects of conditioning time on the flotation of hematite using three technical grade fatty acid reagents as providing additional evidence on their mechanism of interaction with the hematite surface. Various mechanisms have been postulated as occurring as conditioning time is increased. Both physical (e.g. conditioning time and power input) and chemical (nature, dispersion and solubility of the adsorbing species) contribute to the mechanisms of attachment of collector. In this paper, the mechanism of attachment of oleate to hematite can be readily explained by chemisorption, but the mechanism of attachment of lauric acid appears to be physical adsorption at neutral pH. The flotation of hematite with a mixture of tallow-type fatty acids (palmitic, stearic and oleic acids) is very sensitive to conditioning time, and suggests that, even though flotation is very effective at short conditioning times, it is very susceptible to the presence of fines and their associated high surface areas. It is therefore obvious that both the physical and chemical conditions contribute to the mechanisms of adsorption of fatty acids on iron-containing oxide minerals and must be understood in order to optimise the flotation of these minerals in an industrial situation.  相似文献   
3.
白钨矿浮选731捕收剂低温乳化试验研究   总被引:2,自引:1,他引:1  
介绍了731捕收剂在低温条件下试验的情况。试验研究结果表明,采用A和B药剂以5:6的比例混合组成的复合乳化剂对731进行乳化,低温时乳化体系稳定性好,浮选过程中降低乳化731的用量,同时提高了选择性,降低了浮选成本,实现了低温环境下白钨矿正常浮选作业,达到选矿技术攻关指标。  相似文献   
4.
介绍焦化行业钛设备的应用,剖析了分块式钛泡罩塔盘的结构特点,并对其经济性作了分析。  相似文献   
5.
某铅锌矿选矿尾矿综合利用试验研究   总被引:2,自引:0,他引:2  
针对选矿尾矿的特性,采用高选择性的3ACH捕收剂、F—1抑制剂,回收了绢云母含量分别达96%和64%以上的一、二级绢云母产品。经应用试验表明:绢云母一级品在橡胶中的补强性能基本达到了沉淀法白炭黑水平,二级品也全面超过硅铝炭黑的补强性能。  相似文献   
6.
硫酸铵-氯化亚锡-孔雀绿体系浮选分离铂   总被引:5,自引:0,他引:5  
研究了在盐酸介质中硫酸铵存在下氯化亚锡—孔雀绿—水体系浮选分离铂的方法。在最佳实验条件下,铂的浮选率可达100.0%,并与常见贱金属完全分离。  相似文献   
7.
本文研究了二烷基硫代磷酸铵(RO)2PSONH4(R=乙基、丁基、己基、烯丙烯)系列捕收剂对非硫化矿孔雀石、锡石、赤铁矿、白铅矿、方解石和菱锌矿的浮选性能,并就药剂结构与性能关系进行了分析讨论.  相似文献   
8.
赵世民  王淀佐  胡岳华  徐竞 《矿冶工程》2002,22(3):48-50,53
介绍了松香的来源、化学组成及理化性质;讨论了松香及其衍生物在非硫化物矿浮选分离、有色金属离子的浮选分离以及从水溶液中浮选分离有机物等方面的应用情况。  相似文献   
9.
硫化钠在黑白钨加温精选中的应用研究   总被引:3,自引:0,他引:3  
陈文胜 《中国钨业》2002,17(3):26-28,32
介绍了柿竹园黑白钨混合粗精矿加温精选中 ,添加硫化钠与水玻璃混合剂比单一添加水玻璃能更有效地使白钨矿与萤石等含钙矿物及脉石矿物分离。论述了硫化钠在加温精选中的作用效果并探讨了其作用机理  相似文献   
10.
The medium coking coal fines of − 0.5 mm from Jharia coal field were taken for this investigation. The release analysis of the composite coal reveals that yield is very low at 10.0% ash, about 25% at 14% ash and 50% at 17% ash level. The low yield is caused by the presence of high ash finer fraction. The size-wise ash analysis of − 0.5 mm coal indicated that − 0.5 + 0.15 mm fraction contains less ash than − 0.15 mm fraction. Thus, the composite feed was split into − 0.5 + 0.15 mm and − 0.15 mm fractions and subjected to flotation separately. The low ash bearing fraction (− 0.5 + 0.15 mm) was subjected to two stages collectorless flotation to achieve the concentrate with 10% ash. The cleaner concentrate (18.9%) with 10% ash was recovered which has an application in metallurgical industries. The concentrate of 30.2% yield with 12.5% ash could be achieved in one stage collectorless flotation which is suitable for use in coke making as sweetener. As the − 0.15 mm fraction contains relatively high ash, collector aided flotation using sodium silicate was performed to get a concentrate of 23.6% yield with about 17% ash. The blending of this product with cleaner tail obtained from − 0.5 + 0.15 mm produces about 35.0% yield with 17% ash and that can be utilized for coke making. The reject from the two fractions can be used for conventional thermal power plant or cement industries using a 23.5% ash after one stage collector aided flotation and the final tailings produced content ash of 61.6% can be used for fluidization combustion bed (FBC). This eventually leads to complete utilization of coal.  相似文献   
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